In many cases, the production of a concentrate from an ore involves complex steps which include crushing and grinding the ore in a wet mill and separating the concentrate from the tailings through various mechanical, physical or chemical steps (such as screening, gravity separation or flotation, etc.). A large amount of water is used in all these steps. Although the procedure works fairly well, it has been found that, when the ore is crushed and ground in the mill, very fine particles (slime) are produced and liberated. Such slime particles have distinctive physical-chemical properties which interfere with the recovery process because they encapsulate, sometimes in clay balls, appreciable quantities of minerals, metals or small precious stones which are lost in reject tailings.
So far as is known, this problem has not yet been solved in a cost-effective manner. Attempts have been made to solve the problem by massive dilution with water or separate processing of clay balls. However, both of these procedures are expensive and time consuming.
It is therefore an object of this invention to provide a process for the recovery of mineral particles, metal particles or small precious stones from aqueous slimes containing such particles in suspension with slime particles which substantially eliminates the problem described above.